document.write( "Question 1154176: x-y=0
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Algebra.Com's Answer #776558 by ikleyn(52790)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "    x - y = 0      (1)\r\n" );
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document.write( "    x + y = 16     (2)\r\n" );
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document.write( "This system can be solved in two ways.\r\n" );
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document.write( "1.  First method to use is the ELIMINATION method.\r\n" );
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document.write( "    Add equations 1) and (2)  (both sides).\r\n" );
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document.write( "    You will get\r\n" );
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document.write( "    2x = 16;  hence,  x = 16/2 = 8.\r\n" );
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document.write( "    Next, substitute the found value x= 8 into equation (1) to find \"y\".  You will get\r\n" );
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document.write( "    8 - y = 0,  which implies y = 8.\r\n" );
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document.write( "    ANSWER.  The solution to the system is  x= 8,  y= 8.\r\n" );
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document.write( "2.  The second method to use is the SUBSTITUTION method.\r\n" );
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document.write( "    From equation (1), express x = y.   Substitute it into equation (2), replacing \"y\" there.  You will get\r\n" );
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document.write( "    x + x = 16,   or  2x = 16,  which implies  x = 16/2 = 8.\r\n" );
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document.write( "    Then again, you substitute the found value of x= 8 into equation (1)  (same as you do in the solution ABOVE),\r\n" );
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document.write( "    and you get y = 8.\r\n" );
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document.write( "    ANSWER.  The solution to the system is  x= 8,  y= 8.\r\n" );
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\n" ); document.write( "\n" ); document.write( "The given system is one of simplest systems of two equations in two unknowns.\r
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\n" ); document.write( "\n" ); document.write( "Actually,  there are  OTHER  methods to use,  beyond these two;  for example the  DETERMINANT  method,\r
\n" ); document.write( "\n" ); document.write( "sometimes also called  \"the  Cramer's rule\".\r
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\n" ); document.write( "\n" ); document.write( "On solving systems of linear equations in two unknowns see the lessons\r
\n" ); document.write( "\n" ); document.write( "    - Solution of a linear system of two equations in two unknowns by the Substitution method \r
\n" ); document.write( "\n" ); document.write( "    - Solution of a linear system of two equations in two unknowns by the Elimination method \r
\n" ); document.write( "\n" ); document.write( "    - Solution of a linear system of two equations in two unknowns using determinant \r
\n" ); document.write( "\n" ); document.write( "    - Geometric interpretation of a linear system of two equations in two unknowns \r
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\n" ); document.write( "\n" ); document.write( "Also,  you have this free of charge online textbook in ALGEBRA-I in this site\r
\n" ); document.write( "\n" ); document.write( "    - ALGEBRA-I - YOUR ONLINE TEXTBOOK.\r
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\n" ); document.write( "\n" ); document.write( "The referred lessons are the part of this online textbook under the topic \"Systems of two linear equations in two unknowns\".\r
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\n" ); document.write( "\n" ); document.write( "Save the link to this online textbook together with its description\r
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\n" ); document.write( "\n" ); document.write( "Free of charge online textbook in ALGEBRA-I
\n" ); document.write( "https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson\r
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\n" ); document.write( "\n" ); document.write( "to your archive and use it when it is needed.\r
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